Louis feiedmann



Feb. 19, 1929.

L. FRIEDMANN STEM! HEATING INSTALLATION FOR RAILWAY GARS I Filed Aug. 22, 1923 2 Sheets-Sheet.

Invem-Z-or .L-Irz'edmam L. FRIEDMANN Feb. 19, 1929.

STEAM HEATING INSTALLATION FOR RAILWAY CARS Filed Aug. 22, 1923 2 Sheets-5neet 2 III/19.8 .1 -11? Z. edm 11 E7 W Patented Feb. 19, 1929.

UNITED STATES PATENT OFFICE.

LOUIS FRIEDMANN, OF VIENNA, AUSTRIA.

STEAM-HEATING INSTALLATION FOR RAILWAY CABS.

Application filed August 22, 1923, Serial No. 658,810, and in Austria March 20, 1923.

This invention relates to an installation for heating railway and other cars by steam and hot water and particularly to a system in which a main steam pipe is used to convey the steam from the locomotive boiler to the cars, the main steam pipe section of each car being connected to that of the adjacent cars so that an uninterrupted pipe connection extends along the whole train.

It is a well known fact that very large quantities of condensate are continuously formed within said main steam pipe, which generally are allowed to escape to the open air. Separators are inserted to collect said condensate and to drain it. This involves a heavy loss of heat energy and therefore installations have already been proposed to utilize the waste heat in said condensate.

The problem of utilizing the heat in the large quantities of condensate in the main steam pipe as distinguished from the condensate forming in the radiators or other. heating means presents however certain diificulties owing to the liability of such condensate to freeze where it is allowed to enter the radiators at a comparatively low tempera-- ture or to remain in the main steam pipe when not heated. Security against freezing is necessary especially when steam is first admitted to the cold installation and is immediately condensed therein and whenthe steam supply is shut ofi. I

Systems of car heating, hitherto used in which the condensate of the main steam pipe was utilized, did not solve this problem but tried to allow heating by means of the condensate only under special and favourable conditions. The radiators were not perma nently connected to water collectitng chambers in the pipes or separators but special means were arranged either to drain such condensate as fast as it forms through special radiators during a heating period or to admit the condensate to the radiators only when steam had already entered them and was continuously fed together with the condensate. Special means were therefore necessary and special provisions had to be made for the period when steam is first introduced into the cold pipes and radiators.

Now this invention has for its object to solve the above problem with simple and eflicient means which do not necessitate the use of special apparatus and which allow permanent connection of the radiators with water ollecting chambers in the pipe or the sepm rators inserted therein, without danger of freezing, so that the heat of the entire condensate formed in the main steam pipe may be utilized.

A great advantage is thus obtained owing to the very large quantities of condensate formed in the main steam pipe about of the steam admitted being usually condensed which may be cooled down to a temperature much lower than 180 F., a temperature regarded as the limit in all installations hitherto used owing to the fact that the same radiators are adapted to be heated by condensate as long as condensate is available and by steam when the condensate has been discharged. The special radiators and the special installations to be heated by the condensate can therefore be dispensed with.

This result is obtained according to this invention by providing the lowermost or water collecting chamber of the main steam pipe or of a separator inserted therein with two outlet orifices or ports or by connecting said water collecting chamber with achamher or part having two orifices or ports, one of said orifices leading to the pipe connected with the radiators and the other leading to the open air or to some chamber or pipe from whence the condensate may be discharged,

the control of the flow of the heating medium through the first orifice being eflected by the usual thermostatic device, controlling the admission valve of the radiator, while the control of the other orifice is either directly or indirectly dependent on the steam pressure. Indirect influence of the steam pressure may be obtained by means of a device responsive to the steam temperature in the main pipe. Thus the discharge of condensate into the radiators can only be effected it a certain steam pressure (or a certain temperature of the condensate) is prevailing in the main steam pipe as otherwise the second orifice is operative to discharge the condensate. It therefore the steam is cut oil? from the main steam pipe or if during the first part of the heating period the steam admitted to the cold installation immediately condenses in con tact with the cold walls, no condensate can be fed to the radiators but the whole condensate is discharged through the second orifice which is freed by its controlling device. The danger resulting from the fact that such cold water may accidentally be raised and. penetrate into the radiators, for instance by the air driven uitby steam entering the main.

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steam pipe or by some water hammerin and may freeze therein, is thereby entirely e iminated so that the installation is frost-proof in spite of the direct connection of the radiators with the water collecting part of the main steam pipe.

A further feature of the invention consists in the fact that the heat of the condensate may be utilized to a further degree by locating the thermostatic device controlling the admission valve of the radiators in such a manner that it in direct contact with the water cooled down in the radiator. The heat radiating surface of the radiator must of course in, this case be large enough to deal with ver great quantities of condensate and cool it down by radiation to the desired degree.

The invention is illustrated in the accompanying drawings in which Fig. 1 shows a cross section through a railway car provided with a heating installation, in which the radiators are ted from a main steam pipe located underneath the car and in which two separators are inserted, two different modifications of the installation being shown each co-operating with one separator.

Fi 2 shows diagrammatically the heating installation proper of such a car and illustrates another modification of the heating system.

Fig. 3 shows diagrammatically on a larger scale another modification of the heating installation similar to that shown in the left half of Fig. 1, and in which both passages leading from the separator are controlled thermostatically, while Fig. 4: shows diagrammatically on a larger scale the modification of the invention illus trated in the right hall? of Fig. 1.

In the example shown in Fig. l the heating installation of the car comprises a main steam pipe 2, 2, which runs from end to end of the car and is adapted to be connected by suitable couplings to the main steam pipe section of another car, so that there exists an uninterrupted piping from the locomotive boiler to the end of the train.

In each car the main steam pipe is not arranged horizontally but is inclined and slopes towards one or more places, at which separators 1 may be inserted adapted to collectthe condensate formed in the main steam pipe. The separator 1 or the lowest part of the pipe has a water collecting chamber extending beneath the pipe and this chamber is provided with two passages, openings or orifices as illustrated at the right hand side of Fig. l. and in Fig. 4 and is in communication with two passages or orifices. One of said passages 3 leads either directly to the open air or to a duct, channel or chamber communicating with the open air. This passage 3 (Fig. 3) is controlled by a valve 4 operated by a thermostatic device 5 arranged in an adjacent chamber, which is influenced by the temperature of the condensate discharged through the opening 3, or by the vapours emanating from the condensate discharged through the passage 3 on account of the difference of pressure within the separator and the atmospheric pressure in the chamber enclosing the thermostat 5.

As is well known in the art, the thermostatic device for controlling the discharge of condensate is adjusted in such a manner that the valve is open as long as condensate of a temperature below a certain limit escapes through the passage 3, but is closed when the temperature of the condensate or of the va pours emanating therefrom reaches or exceeds a certain limit or if steam from the main steam pipe of a predetermined pressure and therefore also of a predetermined temperature escapes through the passage 3. The valve 4 is therefore closed only if the temperature of the condensate or the pressure of the steam in the main steam pipe whichever is taken as a base has reached a certain predetermined value.

In the modification shown in Fig. 1 a pipe 6 projects into the water collecting part of the separator which is connected on the other hand with the heating installation proper of the car. Instead of providing a pipe projeeting into the lowermost part of the separator, the separator may be provided as illustrated in Fig. 3 with a partition wall provided With a slot or opening at its lowermost part, and the pipe 6 may branch oii from the chamber separated from the main part of the separator by the partition wall at any desired point. This pipe 6 leads to the admission opening 7 provided in a chamber ll which communicates with the radiator pipes 13 of the cars. The opening 7 is controlled by a valve 8, which in its turn is operated by a thermostatic device 9.

In the modification described the chamber 11 is provided with a wall in which a conical nozzle 12 is arranged discharging into a sec ond chamber 11, in which a pressure reduction will be produced on account of the jet is suing from the nozzle. radiator 13 are connected with the chamber 11, the upper end being arranged coaxially with and just behind the nozzle 12 and therefore Whenever steam or vapour is fed to the radiator as in cases when the condensate has been drained, or when vapours are developed from the condensate owing to the difference of pressure, the steam or vapour will circu late continuously until condensed and then leaves the radiator at the opening 10. It is to be noted that in this case the opening 10 is arranged behind the thermostatic device in the directionof circulation and therefore this device will be influenced by the condensate and will operate the valve 8 in such a manner that Whenever condensate is fed from the Both ends of the separator it will leave the radiator only at a predetermined temperature much lower than 180 F.

Fig. 2 shows another modification in which two passages or orifices lead from the lower part of the separator, one of them being the mouth of a pipe 6, leading to the radiator, while the other passage 3 connects the lowest part of the separator directly with the open air. This latter passage is controlled by a valve 4 which is itself spring controlled and the spring tension is adjusted in such a manner that the valve will only be closed when a certain predetermined pressure prevails in the separator and in the main steam pipe. I

The pipe 6 leads to the thermostatically controlled radiator 13, which is arranged and operates in the same way as the like parts in Figs. 1 and 3, with the modification that the outlet opening 10 for the condensate is arranged ahead of the thermostatic device, in the direction of flow, so that the condensate will not influence this device.

The thermostatic device 9 will therefore only be influenced by steam if the whole condensate of the main steam pipe has been drained or by'the vapours emanating from the condensate. The device therefore governs the admission in such a way that the condensate leaves'the radiator at approximately 180 F.

In the modification shown in Fig. 4 the lowermost and water collecting part of the separator 1 in the main steam pipe 2 is provided with a passage leading to the pipe 6 in the-lowest part of which a second passage 3 has been provided. This second opening is located in a lateral or inclined part of the wall of the pipe 6 or of a chamber communieating with the pipe 6 and is controlled by a valve 4. The valve has a stem which is weighted in such a manner that the weight tends to open the valve, which is arranged within the pipe or chamber and is subject to the pressure of the fluid contained therein. The valve 4 is therefore kept closed and overcomes the tendency of the weight to open it as long as a predetermined pressure prevails in the separator 1.

The pipe 6 leads to the radiator orradiators 13 thermostatically controlled by the device 9 which actuates the admission valve 8 controlling the opening 7 to which the pipe 6 leads. This opening leads to a chamber 11 from which the radiator 13 branches off. No means for circulating the heating medium are provided in this case. The radiator has an opening 10 through which the condensate may escape and a further opening 16 through which the condensed vapours or the steam or the condensate of the steam may escape.

In this case the thermostatic device is adjusted in such a manner, that when the radiator is heated by steam, the condensate forming within the radiators is discharged at the The above described heating system operates in the following manner:

When the main steam pipe 2, 2 is fed with steam from the locomotive boiler under normal conditions. a certain pressure will prevail therein which will keep the valve 4 closed.

The condensate Which is continuously formed in large quantities in said main steam pipe, will on account of the sloping of the sections of said pipe collect in the lower part of the separator 1. The temperature of such condensate will correspond to the pressure in such pipe and will be higher than 180 F. under the common conditions of working as the pressure of the steam in the main steam pipe is higher than the atmospheric pressure.

Therefore the passage 3 when controlled by a weighted valve will be closed. whenever the steam pressure exceeds a predetermined value and when controlled by a thermostatic device as shown in Figs. 1 and 3 will be closed when condensate of a temperature exceeding a predetermined value or steam from the main steam pipe is discharged. As the temperature of the condensate is dependent on the steam pressure the thermostatic device is practically also controlled though indirectly by the steam pressure in the main steam pipe. Thus the valve 4 is always controlled by means influenced either by the temperature of the condensate or by the normally prevailing pressure in the main steam pipe, whichever is taken as a base for the proper adjustment.

Under these conditions when steam of the requisite pressure and temperature is flowing through the main steam pipe, the valves 4 are closed by said pressure or by the influence of the temperature corresponding to the pressure and the condensate of the main steam pipe collecting in the separator 1 is fed to the radiators through the pipes 6 which communicate with the lowest parts of said separators 1. Continuous feeding of the condensate to the radiators during a certain time will drain the whole condensate from the main steam pipe and now steam will enter the pipe 6 and will act as heating medium until a sufficient quantity of condensate has again formed and has been collected in the separators. Thus heating is efi'ected alternately with steam and condensate as the case may be.

If now the steam supply to the main steam pipe is cut off the pressure within said pipe 2. 2 will fall to atmospheric and the temperaturn of the condensate will decrease.

There fore the valves l of the separators will open the passages 3 and the condensate will escape into the open. The main steam pipe is therefore drained and is soon free from condensate, so that no damage due to freezing can occur during an idle period of the installation.

If now the main steam pipe is again connected with a supply of steam, the first quantities of steam at the heginnin of the heating operation will condense within the cold main steam pipe, but the valves 4 being still. open will immediately drain. such cold condensate to the open air so that no condensate will be left in the main steam pipe. In spite of the fact that the radiators are permanently connected with. the lowermost part of the separator, these relatively large quantities of cold condensate cannot enter the radiator even if a water hammering or a slight raising of the pressure in the main steam pipe occurs, which will have the tendency to lift the condensate. The radiators are therefore etliciently protected against the admission of these quantities of cold con ilensate. Only when the steam pressure has reached a predetermined value and consequently the condensate has a certain predeteru'iined temperature will the valves 4 be closed and the feed ing of water to the radiators in the interior of the car begin. If the valve 4 is thcrmosta. .ically controlled closing of the valve can only occur if the condensate has reached the temperature to which the thermostat has been set, but which must be about 180 F. and only at this moment feeding of the condensate to the radiators may take place.

The condensate from the main steam pipe is then utilized in the way above described for heating the cars and if the heating or radiating surface is of suitable size the main steam pipe will practically be always free of condensate, which will be drained completely through the radiators.

The condensate will be admitted through the opening 7 to the radiators 13 and this admission is controlled by the thermostat 9 the operation of which does not differ from that of the well known devices in other heating installations. However two different ways of utilizing the heat of the condensate are indicatcd. one of these ways being shown in Fig. 1 (left half) and Fig. 3, the other in Fig. 1 (right half) and Figs. 2 and l.

in the latter case the outlet opening 10 for the condensate is arranged ahead of the thermostatic device 9 in the direction of flow of the heating medium and the heat capacity of the condensate can therefore be utilized down to a temperature of 180 F. or a temperature slightly below this limit. The advantage of this arrangement consists in the possibility of utilizing the heat of the vapors emanating from the condensate, which has been under a pressure higher than the atmospheric in the main steam pipe and is under atmospheric pressure only in the radiators. A certain quantity of vapour Will be developed by this pressure relief and the radiator will therefore utilize the heat of these vapours as well as the heat of the condensate down to approximately 180 F.

If however the opening 10 is arranged behind the thermostat in the direction of flow of the heating medium as shown in Fig. 3 then the thermostatic device will be influenced by the temperature of the escaping water and may be so adjusted that the water escapes at a temperature much lower than 180 F. so that the heat capacity of the water, which is very large, may be utilized to heat the radiator and the economy of the whole installation is largely improved.

What I claim is:

1. In a heating installation for railway cars, a main steam pipe, a radiator communieating therewith, a water collecting chamber in said mainsteam pipe, to collect the condensate formed therein, two discharge passages for the condensate leading from said water collecting chamber, one of said passages establishing communication between the main steam pipe and the radiator and the other passage leading to the open air, and

automatic means for closing and opening the discharge passage leading to the open air adapted to allow discharge of the condensate.

2. In a heating installation for railway cars, a main steam pipe, a separator therein provided with a water collecting chamber, a radiator permanently connected with the said collecting chamber, said chamber being provided with a passage leading to the open air, a valve for controlling the flow of condensate through said passage and control means to open and close said valve dependent onthe temperature of the condensate to be discharged.

8. In a heating installation for railway cars, a main steam pipe and separator therein, provided with water collecting chamber, a thermostatically cont-rolled radiator and means to feed said radiator with the condensate contained in the main steam pipe when available and with steam when no condensate is available, said means comprising a conduit leading from the water collecting chamber, a passage leading from said water collecting chamber to the open air and means for controlling said passage dependent upon the pressure of the fluid in the main steam pipe to cause alternatively either discharge of the condensate to the open air or feeding of the same to the radiator.

4:. In a heating installation for railway cars, amain steam pipe, a separator therein, a radiator, and means to supply the same with condensate from the main steam pipe, comprising a conduit between the main steam pipe and the radiator, a passage leading from said separator and to the open air, a valve controlling the flow of condensate through said passage, a thermostatic device arranged With- 5 in the radiator for controlling the admission of condensate to the radiator, said radiator having an exit opening for the condensate arranged beyond the thermostatic device so as to subject the thermostatic device to the influence of the temperature of the condensate.

In testimony whereof I have hereunto set my hand.

LOUIS FRIEDMANN. 

